1. Field of the Invention
The present invention relates to an external component of an endoscope, and more precisely relates to an external component of an endoscope which is used in a portion of the endoscope which can be brought into contact with a disinfectant during a disinfecting operation after use.
2. Description of the Related Art
External components of an endoscope are made of stainless steel, plastics, or an aluminum alloy, etc. However, the portion of the endoscope, which is brought into contact with a disinfectant during the disinfecting operation after use, must be fully resistant to corrosion.
Among the material mentioned above, stainless steel or some plastics exhibit strong resistance to corrosion without being subject to a surface treatment or the like. However, an aluminum alloy must be subject to a surface treatment to obtain a resistance to the disinfectant.
To this end, the surface of the aluminum alloy base member is subject to a chromating treatment and/or an electrolytic deposition (electro deposition) in an appropriate combination (Japanese Unexamined Patent Publication No. 8-277476, No. 8-308788. No. 8-311695, etc.).
In recent years, a strong disinfectant, such as a hydrogen peroxide based liquid disinfectant has been used to prevent infection from the endoscope. If the endoscope is dipped in the disinfectant and fails to be taken out therefrom for a long time, the aluminum alloy base member which has been subjected to the conventional surface treatment can be corroded by the disinfectant, due to functional deterioration, such as a separation of the coating layer at a corner portion of the base member.
It is an object of the present invention to provide an endoscope external component having a high resistance to corrosion, in which no functional deterioration of an aluminum alloy base member occurs even if it is dipped in a disinfectant, such as a hydrogen peroxide based liquid disinfectant, for a long time.
To achieve the object, according to the present invention, an external component of an endoscope, the external component having an aluminum alloy base member, is provided, wherein the surface of the aluminum alloy base member is subjected to anodic oxidation, and thereafter, is subjected to an electrolytic deposition (electro deposition) thereon.
In an embodiment, the anodic oxidation is carried out to deposit an anodized aluminum layer whose thickness is in the range of 1-50 xcexcm.
The thickness of the electrolytic deposition is preferably in the range of 5-25 xcexcm.
It is preferable that the electrolytic deposition include a micro size of gel mixed therein to enhance the corrosion proof.
In an embodiment, the micro-sized gel is provided with a center core portion of 0.5-3.0 xcexcm and has a diameter of 1.0-10.0 xcexcm.
Preferably, the micro-sized gel is provided with a center core portion of 0.7-2.0 xcexcm and has a diameter of 1.5-6.0 xcexcm.
According to another aspect of the present invention, a surface preparation method for an external component of an endoscope is provided, the external component having an aluminum alloy base member. The method includes subjecting an anodic oxidation treatment to the surface of the aluminum alloy base member; and subjecting an electrolytic deposition treatment to the surface on which the anodic oxidation treatment is subjected.
The present disclosure relates to subject matter contained in Japanese Patent Application No.11-267930 (filed on Sep. 22, 1999) which is expressly incorporated herein by reference in its entirety.